The present invention relates to an air-conditioning system in which a dehumidification operation can be achieved during a heating operation and a cooling operation.
In a prior-art air-conditioning system as disclosed in Japanese Patent Unexamined Publication No. 59-180253, a first heat exchanger, a second heat exchanger and a fan for generating air flow are arranged in a room to be air-conditioned. The first heat exchanger and the second heat exchanger are positioned in series in a direction of the air flow by the fan and are received by a unit. In a cooling operation of the prior-art air-conditioning system, a high-pressure and high-temperature refrigerant which has not been substantially cooled and adiabatically expanded after being compressed is supplied to the first heat exchanger and a low-pressure and low-temperature refrigerant which has been substantially cooled and adiabatically expanded after being compressed is supplied to the second heat exchanger. In a heating operation of the prior-art air-conditioning system, the low-pressure and low-temperature refrigerant which has been substantially cooled and adiabatically expanded after being compressed is supplied to the first heat exchanger and the high-pressure and high-temperature refrigerant which has not been substantially cooled and adiabatically expanded after being compressed is supplied to the second heat exchanger.